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121.
The standard therapy for episodes of severe acute inflammatory demyelinating disease of the central nervous system is high dose intravenous corticosteroids. A small proportion of patients fail to improve with this regime and their prognosis can become grave. A recent sham controlled double blind crossover trial in this group of patients demonstrated a significant benefit from plasma exchange. We report six patients with severe acute steroid-insensitive inflammatory demyelinating disease of the central nervous system treated with plasma exchange. We observed a clear improvement in five of these six patients. Whilst complications of plasma exchange occurred these did not outweigh the benefits. Our study supports the use of plasma exchange in severe acute steroid-insensitive inflammatory disease of the central nervous system.  相似文献   
122.
Insulin-like growth factor-I (IGF-I) is widely expressed in the central nervous system (CNS). Whereas during normal development IGF-I is expressed predominantly by neurons and to a much lesser degree by glial cells, its expression in astrocytes, and often in microglia, is increased during and/or after variety of CNS injuries. Recently we have generated a new line of IGF-I Tg mice, called IGF-I(Ast/Tet-Off) Tg mice, in which IGF-I transgene is expressed specifically in astrocytes and is tightly controlled by the tetracycline analog doxycycline. In this study we examined whether IGF-I derived from astrocytes is capable of promoting neural cell growth during development. When the IGF-I transgene is allowed to be expressed, IGF-I(Ast/Tet-Off) Tg mice exhibit markedly increases in 1) brain weight; 2) brain DNA and protein abundance; and 3) number of neurons, oligodendrocytes, and astrocytes, as well as myelination, findings similar to those observed in our other lines of Tg mice that express IGF-I transgene predominantly in neurons. Unlike Tg mice with neuron-specific IGF-I expression, which manifest marked increases in the concentrations of oligodendrocyte/myelin-specific proteins, however, IGF-I(Ast/Tet-Off) Tg mice exhibit an increase in the concentration of glial fibrillary acidic protein, an astrocyte-specific protein. Furthermore, when transgene expression is blunted, brain overgrowth in IGF-I(Ast/Tet-Off) Tg mice ceases. Our data indicate that astrocyte-derived IGF-I is capable of promoting neural cells growth in vivo. Our data also suggest that IGF-I's actions in CNS depend in part on the location of its expression and cellular microenvironment and that continuous presence of IGF-I expression is necessary for brain overgrowth.  相似文献   
123.
The aim of this study was to evaluate the effectiveness of the addition of manual-based cognitive-behavioral therapy to a medication regimen of clomipramine and fluoxetine and the withdrawal of medication during cognitive-behavioral therapy. The participant was an 11-year-old girl with symptoms of obsessive thoughts about germs and illness and handwashing compulsions. The addition of cognitive-behavioral therapy reduced the participant's daily number of obsessions and avoidance behaviors after three sessions. When medication was tapered during the cognitive-behavioral therapy program, the participant's symptoms continued to decline, and after treatment, she no longer met diagnostic criteria for obsessive-compulsive disorder. Impressively, the participant remained medication free and treatment gains were maintained at 4 months' follow-up.  相似文献   
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125.
Endoscopically placed nitinol stents for pediatric tracheal obstruction   总被引:1,自引:0,他引:1  
OBJECTIVE: To provide preliminary clinical data regarding endoscopically placed nitinol stents for children with tracheal obstruction as a temporizing measure to allow for trach tube decannulation while awaiting growth to allow for tracheal resection. METHODS: This case series describes the experiences of two children (ages 5 and 15) who were dependent upon tracheotomy because of acquired tracheal obstruction. Both patients had combined tracheomalacia and tracheal stenosis. After failing tracheoplasty with rib graft augmentation both patients suffered from extensive tracheal disease, which was too long to allow for immediate tracheal resection. INTERVENTION: Endoscopic placement of nitinol stents in the obstructed tracheal segment using fluoroscopic guidance. All tracheotomy tubes were removed immediately after successful stent deployment with the patient still under general anesthesia. RESULTS: Four stents were placed in total. The first patient's initial stent was too narrow and was, therefore, removed and replaced at a later date with a larger diameter stent. The second patient experienced distal migration of his initial stent requiring stent removal and replacement at a later date. Both patients remain successfully decannulated (follow-up, 25 and 26 months) and are currently living more normal lives as they grow and await tracheal resection. CONCLUSION: Preliminary use of nitinol stents for pediatric tracheal obstruction has enabled successful decannulation in two children with complicated airways. Our results with this series of patients suggest that nitinol stents can be safely used in children as a temporizing measure until tracheal resection can be safely performed. With this approach children can live free from the hassles of trach care, social isolation and peer ridicule. Limited pediatric experience exists in the literature about nitinol stents. Thus, our experience with stent selection and placement will help others avoid problems encountered in this initial series.  相似文献   
126.
Environmental pollution that renders waters along the coastline and beaches unsatisfactory for use by the general public has become a global health problem. This study was conducted to examine the effects of pollution of beach waters and sediment at seven selected locations receiving land drainage along a 45-km stretch of the east coast near Visakhapatnam, India. Pathogenic bacteria were identified using standard methods of culturing on selective media. The Pollution Index (PI) was determined as the ratio of fecal coliform/fecal streptococci. Protozoan cysts and helminth ova were also identified by microscopic examination of water after appropriate staining. The results suggested that the beach waters in Visakhapatnam are hygienically poor. A high PI of the water in Lawson's Bay indicated that the water was unsuitable even for noncontact recreation (boating, etc.). Pathogen densities dissipated considerably from the source to the low tide mark. Sediments had significantly higher bacterial and protozoan populations but pathogen concentrations were low except in heavily used areas. The general distribution pattern suggests that the nature of the sediment has a significant role in the retention of bacteria, protozoan cysts, and soil-transmitted helminths.  相似文献   
127.
We have investigated the influence of hypoxia on the radiosensitivity of 4 early-passage tumor cell lines that were established from malignant glioma patients at our Institute. These cell lines were M006, M059J (a highly radiosensitive line), M059K (a radioresistant line derived from the same biopsy as M059J), and M010b. The GM637 human fibroblast cell line was used as a normal control. The oxygen enhancement ratios (OERs) for these cell lines, determined using a clonogenic survival assay, were approximately 3.6 (GM637), approximately 3.7 (M006), approximately 2.5 (M010b), approximately 2.1 (M059K), and approximately 3.5 (M059J). The broad range of OERs for these glioma lines was not related to cellular glutathione levels or to differences in intrinsic cellular radiosensitivity. Because studies with rodent cell lines indicate that defects in certain DNA repair genes, including ERCC1, can greatly influence cellular OERs, and because several such repair genes, including ERCC1, localize to a region of chromosome 19q that is close to a common deletion in human glioma, we reasoned that such deletions might contribute to the diverse OERs of these tumor cell lines. However, measurements of ERCC1 protein levels using immunofluorescence staining or Western blotting, of ERCC1 mRNA levels using Northern blotting, and of functional nucleotide excision repair capability using the UV/adenovirus reactivation assay, failed to indicate any deficit in these activities. Thus, although the effect of hypoxia on the radiosensitivity of different human glioma cell lines can vary widely, the mechanism of this effect remains unknown. The potential implications of this finding for radiation therapy, and especially for hypoxia imaging-guided intensity-modulated radiation therapy (IMRT) treatment planning, are discussed.  相似文献   
128.
129.

Objective

Successful weight loss interventions for African-Americans adolescents are lacking. Cognitive-behavioral interventions seek to develop weight loss skills (e.g., counting calories, goal setting, managing one's environment). Little is known about how well adolescents implement such skills in their daily lives. Study aims were to (1) examine weight loss skills utilization at midpoint and end of a 6-month cognitive-behavioral/motivational interviewing weight loss sequential multiple assignment randomized trial (SMART), and (2) determine if greater skill utilization predicted weight loss at treatment end and 3 months post-treatment.

Method

One hundred and eighty six African-Americans adolescents with obesity and their caregiver were first randomly assigned to complete 3 months of cognitive-behavioral and motivational interviewing family-based weight loss treatment in their home or in the research office (Phase 1). Nonresponders (i.e., those who lost < 3% of initial weight, n?=?161) were rerandomized to 3 months of continued skills training (n?=?83) or contingency management (n?=?78) for Phase 2; responders were allocated to 3 months of relapse prevention (n?=?20). Adolescents’ frequency of weight loss skills utilization was assessed via questionnaire at treatment midpoint and end.

Results

Higher treatment attendance was associated with better skill utilization. Higher skill utilization was associated with more weight loss at treatment end, whereas higher baseline confidence was associated with more weight loss at follow-up.

Conclusions

This study indicates the importance of attending weight loss intervention sessions to develop and strengthen weight loss skills in African-American adolescents with obesity, and strengthening confidence to use such skills for continued weight loss.  相似文献   
130.
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